Amazon has STA-BIL 22205 Fuel Stabilizer – 4 Fl oz for $1.96. Shipping is free for Prime members or while Subscribe and Save is available.
https://www.amazon.com/STA-BIL-22…ive&sr=1-1
Alternatively, it is available at Walmart for $1.96. Choose free store pickup otherwise shipping is free on orders $35+.
https://www.walmart.com/ip/seort/…gIMVfD_BwE